Originally from the Harry Potter fan-made play, "A Very Potter Sequel" (the Sequel to AVPM). Based on the character Dolores Umbridge in the Potter books, it is played by a musculuar man in a dress in the play who claims to be the neww "mama" of Hogwarts. In real life, it is the one straight guy who's female friends take total advantage of him in many different ways.
Female friend: Mama, you wanna go to the school and but me a breast cancer cookie?
Mama Umbridge: Sure, I'll be back in a minute.
-While gone, female friends relinquish Mama's seat to an intimidating looking upper classman- Mama returns with cookies for everyone at the over crowded lunch table-
Mama Umbridge: Hey, what happened to my chair?!?
Female friend: That guy took it.
Mama Umbridge: I'll just stand.
Female Friends: And a very lovin' and carin' Mama he is!